Need to replace Hard Drive on G56 notebook

I have a hp g56 108sa notebook. I have had the hard drive replaced once under warranty and it has failed once again but I dont wish to wait 10 days for it to be replaced again so I want to get a new hdd but with a bigger capacity(mine is 250gb and I am looking ay purchasing a 320gb one, and I wish to replace . Is this feasible?

I have ordered some recovery discs from hp partners as I foolishly didnt create any when I had the chance. The reason I am asking this question is that I have read that other people have had problems replacing original hdd`s with bigger ones on laptops